Diastolic heart failure (DHF), a subset of congestive heart failure (CHF), is a clinical syndrome resulting from any structural or functional cardiac disorder that impairs the ability of the ventricle relax properly and fill with blood. The hospitalization rate of the patients suffering from DHF diastolic heart failure is similar to the hospitalization rate of patients suffering from systolic heart failure (SHF—a condition in which the heart is not contracting efficiently).
Primary diastolic dysfunction is typically observed in patients with hypertension and hypertrophic or restrictive cardiomyopathy, but can also occur in a variety of other clinical disorders and has a particularly high prevalence in the elderly population. Aging is associated with ‘physiologic’ diastolic dysfunction due to the increase in left ventricle muscle mass and/or changes in passive elastic properties of the myocardium, hence, the concern of an increase in the incidence of diastolic dysfunction as the aging of the western world population progresses.
To one of ordinary skill in the art, there is thus a need for, and it would be highly advantageous to have a method and device for improving heart ventricular function. Moreover, there is a need for such a method and device which is biocompatible and is specially configured for compact and long-term reliable use in humans.
Various in-vivo methods and devices for improving diastolic function of the heart are described in international patent applications Nos. PCT/IL02/00547 (WO 03/007778), PCT/IL05/01014 (WO 06/03310), PCT/IL04/00986 (WO 05/041745), PCT/IL04/00072 (WO 04/066805), PCT/IL2007/001180 (WO 08/038276) of the same assignee hereof, the descriptions of which are incorporated herein by reference. The aforementioned international patent applications describe elastic means used for improving diastolic function of the left ventricle of the heart by pushing and/or pulling, an inner and/or outer wall region respectively of the ventricle during the cardiac cycle while minimally disturbing the heart function. The operation of the devices described in these publications is based on storing energy from the myocardium during the systole and releasing it during diastole, thereby making it available to augment diastolic performance.
The present invention provides a device and a method for implanting it inside the left ventricle cavity, for assisting left ventricular function of the heart, which may be used independently, or in combination with imaging modalities such as Echocardiography and/or X-Ray Fluoroscopy.
It is therefore an object of the present invention to provide a method and device for augmenting diastolic performance in diastolic heart failure (DHF) patients.
It is another object of the present invention to provide a method and apparatus for implanting the ventricular function assisting device of the invention.
It is a further object of the present invention to provide minimally invasive methods for implanting the ventricular function assisting device of the invention through trans apical approach or through catheterization.
It is yet another object of the present invention to provide an imaging method and technique for guiding the implantation of the ventricular function assisting device of the invention in the left ventricle based on the inner morphology of the ventricle.
Other objects and advantages of the invention will become apparent as the description proceeds.
It should be noted that the embodiments exemplified in the Figs. are not intended to be in scale and are in diagram form to facilitate ease of understanding and description.